Toine, I was having a similar problem with my istDS and A50/1.4 when shooting wide open in low light. I relied on the focus indicator for confirmation, which isn't reliable in low light levels (below f4, by some accounts). Switched to using my eyeballs and brain to confirm focus - much better.
Tim Toine wrote:
I have noticed that many of my istD shots in manual focus are slightly out of focus. The area in focus is "always" in the background of the spot I focused on. Now I'm wondering if I need to blame my eyes, the +/- slider of the eyepiece, the mounting of the focusing screen, maybe the ccd alignment??? Toine
